1. Technical Field
The present invention relates to an optical detection device, a display device, and an electronic apparatus.
2. Related Art
Recently, a display device provided with a position detecting function in which a touch panel is disposed on the front side of a display unit has been used in electronic apparatuses such as cellular phones, personal computers, car navigation devices, ticket-vending machines, and banking terminals. With such a display device, a user can touch an icon or the like included in a display image or input information while referring to the image displayed on the display unit. Exemplary known position detecting methods using such a touch panel include resistance and capacitance types.
On the other hand, the display area of a projection-type display device (projector) or a display device for a digital signature is wider than that of the display device of a cellular phone or a personal computer. Accordingly, in such display devices, it is difficult to realize position detection using the resistance-type touch panel or the capacitance-type touch panel described above.
Known general technologies relating to a position detecting device used for a projection-type display device include, for example, the technologies disclosed in JP-A-11-345085 and JP-A-2001-142643. However, in this type of position detecting device, there are problems such as an increase in the size of the system.